Surveying instrument.



J. S. ADAMS.

SURVEYING INSTRUMENT.

APPLICATION man APR.28, 1915.

1,174,034. Patented Mar. 7, 1916.

JAMES s. ADAMS, FI-1ASLAM,'TEXAS.

sunvnvme, INSTRUMENT.

Specification of Letters Patent. Patented. Egan '7 1916,

, Application filed Atrn 28, 1915. Serial no. 24,51o'.

To all whom at mag/concern:

Be it known thatI," JAMES S; ADAMS, a citizen of the United States,residing at Haslam,in the county of Shelby and State of Texas, haveinvented certain new and use ful Improvements in Surveying Instruments,of which the following is, a specification. w

This invention relates to precisioninstruments and more particularlyrelates to an instrument of this character which may be em ployed bysurveyors in calculating the dis- .tance between the point ofsetting upand the target, without the use of the usual-lin ear chain, I f I As aprincipal object it is contemplated to provide a surveying transitbearing a pair of pivoted telescopes, one of which is employed to findthe elevation of the target by reference to a guide scale while .theother telescope coacts with the one first mentioned in automaticallyregistering the distance between the point of set-up andthe target.

More specifically it is aimed to provide a base plate which may befitted upon the ordinary tripod, such plate to have pivotally mountedthereon an elevational telescope for there is illustrated the preferredembodi-f ment of this invention, as it is reduced to practice andthroughout the several views of which like characters of referencedesignate similar parts: Figure 1 is a plan view of the transit providedby this invention, Fig. 2 is an elevational view of the subjectmatter ofFig. 1, Fig. 3 is a sectional detail of the adjusting means for thedistance telescope, and Fig. 4 is a side elevational view of theadjusting means for the elevation telescope.

There is employed in the transit ofthe,

present invention a base plate 5 which is i earns PATEN WEE,

substantially rectangular but havingone of itsends 6 prolonged to meetthe diagonal member, 7 in forming an extended corner from whichprojectsthearm 8, parallelto the sides of the plate 5. This arm isformed with a slot 9 in which there is slidably accommodated a blocklO,such block being" adjustably movable longitudinally of the slot by meansof the screw 11, oneterminal of which is fitted with the knurled cap 12while the opposite end is cut away at the point denoted 18 toaccommodate in the cut away portiona screw 14, which a reference to Fig.3 will show as permitting rotation ofthe screw without longitudinalmovement thereof. 5

I At some suitable" point of the base plate which may be symmetricallydetermined in accordance withthe weight of the telescopes mounted uponsaid plate, there may be provided the removable pivot screw 15 whichrotatably mounts the base plate 5 upon a hub 16 carried upon the upperplatel? of a tripod designated 18 as an entirety. This tripod has alower plate 19 vertically spaced from the mentioned upper plate 17 andadjustably maintaining the same through the medium of thecustomaryscrews 20 where by leveling of the base plate 5 is attained inaccordancewith spirit levels 21 which may be inset into the plate5at'right angles to each other. supported'upon this base plate forturning respectively through vertical and horizontal angles. Theelevation telescope 22 is pivoted to one of the forward corners of theplate through the medium of a yoke 23 and is provided rearwardly withthe lateral extension 24 which may be threaded to; re- I ceive at itsextremity the adjusting friction cap 25 which will maintain thetelescope in set position with reference to the arcuately slotted guide26 through which the extension 24: projects. This guide isprovided witha scale denoted 27 with which a pointer 28 carried by the telescope isadapted to co,-

act in determining degrees of angular 'ele vation ofa target. Acompass'29 may also be supported by the base plate at some suitable point.

The distance" registering telescope 30 s also mounted for passingthrough vertical v, angles through the medium of the pivoting. yoke 31,itself swivelly mounted upon the base plate 5. Rearwardly thisinstrument is Two telescopes are pivotally 1 supported by the ring 32secured at the upper extremity of an adjusting rod 33, this latter beingthreaded for vertical movement;

through the block 10 previously described as slidable in the slottedprojection. 8. A nut 3a controls 'vertical adjustment of this rod and apointer 35 is carried by the block 10 to coact with the scale 36engraved on one upon by adjusting opposite screws 20 in the usualmanner. The elevation telescope 22 is then trained upon the target whichmust be brought to the exact center of vision in the field afforded bythe, cross hairs of the telescope. The elevation may then be read offupon the scale 27 the latter being suitably laid oil in both directionsfrom the zero point which the pointer 28 normally indicates when thetelescope is level, those readings on the portion of the scaledesignated A being plus elevations while the upper portion 13 of thescale is read for the minus elevations, or depressions from thehorizontal line of sightthrough this telescope. WVhen the elevation hasbeen thus determined both the telescope 22 and the base plate 5 areclamped in their positions while the target is then located through thedistance tele-' scope 30 so that the line of sight now taken intersectsthe line of sight of the elevation telescope at the target itself. Areading is then taken upon the scale 36, the graduations of which areespecially calibrated for each transit. It will thus be seen that meanshave been provided whereby the objects previously presented may bereadily attained by this novel embodiment of transit. Aside fromsurveying the distance across impassable bodies such as quicksand, widerivers and the like and in otherwise dispensing with the use of theusual chain, this invention provides a precision instrument which may bemost readily adapted for use as a range-finder. 7

While in the foregoing however, there has i thus been illustrated in thedrawings and described in the specification such combination andarrangement of elements-as constitute thepreferred embodiment of thisinvention, it is desired to emphasize the fact that such minor changesin the matters of proportion and degree may be made in later adaptationsof this device as shall not alter the spirit of the invention as definedin the appended claims.

What is claimed is: v

1. A surveying instrument including a-rotatable base plate, means forleveling and holding said plateagainst rotation, yokes mounted onopposite sides of said plate, a telescope pivotally supported in eachyoke for movement through vertical angles, an arcuate scale frictionallysupporting the rear of 0116015 said telescopes,a pointer carried by thelatter to coact with said scale, a vertically adjustable rod supportingthe other of said telescopes, and means for turning said rod throughhorizontal angles.

2. A surveying instrument including a rotatable base plate, means forleveling said plate and holdingthe same against rotation, yokes carriedby said plate and one thereof swivelly connected thereto, a telescopepivof said telescopes for movement through both vertical and horizontalangles.

3. A surveying instrument including a rotatable base plate, means ascustomary for leveling said plate and holding the same againstrotation,a pivoting yoke carried by said plate, a swiveled pivoting yokealso carsupporting the free extremity of the other ried thereby, anarcuately slotted guide secured to said plate, a telescope mounted infirst said yoke for movement through vertical'angles, an extension uponsaid telescope for projection through said guide, said guide having ascale marked thereon, a pointer carried by said telescope, means for:tric'tionally clamping said telescope to said guide, a slottedextension formed on one corner of said plate, a block slidablehorizontally in said extension, a telescope mounted in said second yokefor horizontal movement, an adjustable rod passing through said blockand also supporting second said telescope, said slotted extension havinga scale marked thereon, and a pointer carried by said block to coactwith said scale.

In testimony whereof I afiix my signature in presence of two witnesses.

- JAMES s. ADAMS. Witnesses C. M. SAroN, W'. P. MoGEE.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. c.

